Apparatus for receiving metalworking fluid

ABSTRACT

An apparatus 46 for receiving metalworking fluid from a sump 12 of a machine 10 is disclosed. Various construction details are developed which provide for the collection of fluid and increasing the concentration of tramp oil in the collected fluid. In one embodiment of the invention, the apparatus includes a colllection chamber 48 having an interior 54 which is in flow communication through an opening 58 in a wall 56 of the chamber with the top most layer of the metalworking fluid.

CROSS-REFERENCE TO RELATED APPLICATION

This application relates to copending U.S. application Ser. No.08/998518, pending entitled "Method for Processing Metalworking Fluid,"by David R. Fortier, and copending U.S. application Ser. No. 08/997939,pending entitled "Apparatus for Processing Metalworking Fluid," by DavidR. Fortier.

TECHNICAL FIELD

This invention relates to an apparatus for processing metalworkingfluids used with tools for removing metal, and, more particularly for amethod of processing the fluid to remove contaminants and retard thegrowth of bacteria.

BACKGROUND

Metalworking processes use machines having cutting tools, grindingdevices or other tools to remove metal from a workpiece. These toolsgenerate heat by sliding friction at the interface between the tool andthe workpiece. Metalworking fluids are sprayed on the interface to washaway chips, improve surface finish, increase tool life, reduce the powerrequired and to cool the tool and the workpiece. These fluids arecommonly called coolant because cooling is one of the major functions ofthe fluids.

There are a wide variety of metalworking fluids including compoundedmineral oils, fixed and sulfurized oils, and water and oil emulsions.Emulsions of water and water soluble oil are one class of metalworkingfluids widely used for metalworking processes. The emulsion resemblesmilk in appearance, is not expensive and has low viscosity permittingthe emulsion to separate readily from the chips. In addition, theemulsion has good coolant properties for removing heat from the tool andwork piece to keep their temperatures within acceptable limits.Unacceptable levels of temperature in the cutting tool or the work piececan result in deterioration of both the work piece and the cutting toolultimately resulting in failure of the cutting tools or irreparabledamage to the work piece.

In one application, an emulsion of 95% water and 5% lubricating oil issprayed on the tool and on the workpiece. As the metalworking fluid issprayed on the workpiece and cutting tool, the metalworking fluidperforms its functions, such as cooling, and drains to a fluid sump. Thesump is disposed beneath the machine and collects the metalworkingfluid, along with chips and other debris carried by the fluid. The fluidalso carries tramp oil which has leaked from gear boxes andtransmissions on the machine, or which has lubricated sliding surfaceson the ways, and which was protecting the workpiece from corrosion priorto a machining operation. The tramp oil floats on the surface of thefluid in the sump.

The metalworking fluid contaminated with tramp oil is creates an idealbreeding place for anaerobic bacteria in the sump. The tramp oil forms alayer on the top of the fluid, sealing the fluid from contact withoxygen in the air. The bacteria breed, consuming the tramp oil fornourishment and ultimately degrading the quality of the fluid to such anextent that it no longer performs it useful function and turns rancid.The fluid is then discarded.

One approach to removing the tramp oil is to dispose a conduit having afloating inlet within the upper layer of fluid in the sump. The floatinginlet is in flow communication with a separator for separating tramp oilfrom the fluid. The separator typically has a tortuous flowpath alongwhich the fluid is flowed. The flow path leaves the tramp oil in aseries of pools at the top of the separator, separating the tramp oilfrom the fluid. The tramp oil is removed and the now, less contaminatedfluid returns to the sump. Occasionally, the floating inlet for theseparator conduit sinks below the surface of the fluid in the sump andprimarily returns pure fluid to the separator leaving the tramp oil onthe top layer of the fluid with the unfortunate results described above.

Accordingly, personnel working under the direction of Applicant'sassignee have sought to develop a fluid processing system which wouldseparate tramp oil from the fluid and retard the growth of anaerobicbacteria within the fluid.

SUMMARY OF THE INVENTION

This invention is in part predicated on the recognition that removal offluid from a metalworking fluid sump provides an opportunity to increasethe level of tramp oil in the fluid sent to a separator and to aeratethe fluid removed from the sump for circulation back to the sump andblock the formation of anaerobic bacteria.

According to the present invention, an apparatus for receivingmetalworking fluid from a sump has a collection chamber in flowcommunication through an opening that receives fluid from the upperlevel of the working fluid in the sump to insure the concentration oftramp oil in the collected fluid is greater than the concentration oftramp oil in the sump.

In accordance with one embodiment of the present invention, at least oneorifice for sucking fluid out of the collection chamber is disposed at alevel which is below the level of the lower surface of the opening butin close proximity to the opening to further increase the concentrationof tramp oil in the fluid withdrawn from the chamber.

In accordance with one detailed embodiment of the present invention, theorifices are sized to provide vortexes under normal operative flowconditions to cause the fluid to circulate circumferentially in thecollection chamber and to entrain air into the fluid to adversely affectanaerobic bacteria in the fluid.

In accordance with one detailed embodiment, a plurality of orifices aredisposed in the chamber such that vortices formed by the orificesincrease the circumferential circulation of fluid in the chamber toconcentrate tramp oil at the axis of the cylindrical chamber.

A primary feature of the present invention is a collection chamberdisposed in a sump. The collection chamber has an opening. Anotherfeature is the level of the opening which is adjacent the upper level ofthe working medium fluid in the sump. In one embodiment, the opening isin flow communication with at least the top most inch of the fluid inthe sump.

A primary advantage of the present invention is the amount of tramp oilremoved from the sump per unit of time which results from increasing theconcentration of tramp oil flowed to the separator. Another advantage isthe level of anaerobic bacteria in the working medium fluid whichresults from introducing oxygen into the fluid by aerating the fluid asit is withdrawn from the collection chamber. Still another advantage isthe dependable removal of working medium fluid having tramp oil whichresults from the collection chamber always being in flow communicationwith the top most layer of tramp oil in the sump under normal operativeconditions that require only that the level of coolant in the sump bemaintained within accectable tolerances.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a machine for metalworking having a sumpdisposed beneath the machine for receiving metalworking fluid.

FIG. 2 is a perspective view of the machine shown in FIG. 1 with themachine shown in phantom, and shows the sump and fluid distributionsystem for the sump which is disposed in the sump.

FIG. 3 is a schematic representation of an apparatus for processingmetalworking fluid which includes the sump and the embodiment of thefluid distribution system shown in FIG. 2.

FIG. 4 is a side elevation view of a collection chamber partially brokenaway to show a conduit and an orifice disposed in the collectionchamber.

FIG. 4A is a top view of the collection chamber with lines of flow ofthe metalworking fluid shown by arrows.

FIG. 5 is a side elevation view of an alternate embodiment of thecollection chamber shown in FIG. 4.

FIG. 5A is a top view of the embodiment of the collection chamber shownin FIG. 5.

FIG. 6 is an alternate embodiment of the apparatus for processingmetalworking fluid shown in FIG. 3.

BEST MODE FOR CARRYING OUT THE INVENTION

FIG. 1 is a perspective schematic, view of a machine 10 formetalworking. The machine has a sump 12 disposed beneath the machine forreceiving metalworking fluid. The machine has a spray system (not shown)for spraying metalworking fluid on a workpiece (not shown). Asubstantial portion of the metalworking fluid for the spray system isdisposed in the sump 12 beneath the machine where it is recirculated bythe spray system.

FIG. 2 is a perspective view of the machine 10 shown in FIG. 1 with themachine shown in phantom. FIG. 2 shows the sump 12. A fluid distributionsystem 14 for the sump is disposed in the sump beneath the machine. Thefluid distribution system is disposed below the surface level S of thefluid. The sump has regions of fluid circulation under operativeconditions which include at least one region R of potentially lowercirculation. The regions of potentially lower circulation result fromthe contour of the sump and portions of the machine which extend intothe sump. These create zones of little or no circulation unless thefluid is positively circulated by the fluid distribution system.

FIG. 3 is a schematic representation of an apparatus 18 for processingmetalworking fluid which includes the sump 12 and the embodiment of thefluid distribution system 14 shown in FIG. 2. As shown in FIG. 3, theapparatus for processing metalworking fluid includes a separator 22 forprocessing metalworking fluid that has tramp oil. The separator issimply represented as a tank 24 having an inlet chamber 26 and an outletchamber 28. A continuous flow path 32 for the metalworking fluid extendsthrough the tank. Downwardly projecting baffles 34 and upwardlyprojecting baffles 36 define the flow path. The baffles divide the tankinto a plurality of separation regions 38 each having a pool 39 at thetop of the separation region. The pool has a collection chamber 40disposed in the separator. One acceptable separator is the Tramp Champmodel separator, available from Porter Systems, Inc., P. O. Box 535,Bridgeport, N.Y. 13030.

The apparatus 18 for processing metalworking fluid includes acirculation system 42. The circulation system is in flow communicationwith the separator 22 and the fluid distribution system 14 for the sump12. The circulation system removes metalworking fluid from the sump,flowing an amount of fluid per unit time from the sump. A first amountper unit time is sent to the separator. A second amount per unit timeby-passes the separator 22 and is sent directly to the fluiddistribution system 14 in the sump.

The circulation system 42 uses one or more pumps 44 for flowing themetalworking fluid through the system. In the embodiment shown, a singlepump is used with appropriate valving V1, V2, V3. Pumps in fluidcommunication with two or more of the conduits or disposed in the fluiddistribution system in the sump 12 are equivalents of the one or morepumps shown in FIGS. 3 and 5.

The circulation system 42 includes an apparatus 46 for receiving(collecting) metalworking fluid. The apparatus includes a collectionchamber 48 and at least one collection orifice 52 or more as shown inFIGS. 4-5A. The orifice is at the collection chamber and may be separatefrom the collection chamber or formed integrally with the collectionchamber, such as by simply boring a hole in the chamber.

The collection chamber 48 is disposed in the pool of metalworking fluidin the sump 12. The collection chamber has an interior 54. The interioradapts the chamber to receive metalworking fluid having a higherconcentration of tramp oil than the adjacent fluid in the sump 12 (thatis, the concentration of tramp oil per unit volume of metalworking fluidin the collection chamber is greater than the concentration of tramp oilper unit volume of fluid in the sump less the amount of working fluid inthe collection chamber).

The interior 54 having a collection region 55 of the chamber is boundedby a wall 56. The wall has at least one opening 58 at a level which isapproximately equal to the level of fluid (height H of fluid) such thatan upper portion of fluid in the sump flows into the collection chamber48 through the opening 58.

One or more first collection conduits 62 are in flow communication withone or more collection chambers 48. All conduits, such as conduit 62,have an associated flowpath designated by the addition of the letter f(62f). Each collection conduit has at least one leg 64 in flowcommunication through the collection orifice 52 and with the interior 54of the collection chamber. The collection conduit has an adjustablevalve V1. The pump 44a has a first inlet 66 in flow communication with acollection conduit 62a for another sump (not shown). A second inlet 68is in flow communication through the first collection conduit with thesump 12. The pump has one or more outlets such as the first outlet (notshown) for pressurized flow to the sump 12, a second outlet 72 forpressurized flow from the other sump to the separator 22 and a thirdoutlet 74 for pressurized flow to the separator. A second separatorconduit 76 places the outlet 74 of the pump in flow communication withthe inlet 26 to the separator 22. A third return conduit 78 extends fromthe separator for returning metalworking fluid to the sump 12 with asmaller concentration of tramp oil than the concentration of tramp oilin the fluid of the sump. A fourth return conduit 82 is in flowcommunication with the collection conduit through the outlet of thepump. The fourth return conduit supplies pressurized flow to the fluiddistribution system 14 through the valve.

The fluid distribution system 14 in the sump 12 has a first conduit 84and a second conduit 86 in flow communication with the fourth returnconduit 82. The fluid distribution system supplies pressurized fluid tothe sump 12. The first conduit has a first leg 88 having a flow path 88fwhich extends into a region of naturally lower circulation of the sump.The first leg of the conduit has a plurality of exit orifices, asrepresented by the arrows 92 (angled at an angle of twenty (20) degreesto the direction of the flowpath in a horizontal plane and at an angleof twenty to twenty-five (20-25) degrees upwardly in a vertical plane).The exit orifices direct fluid away from the conduit and upwardly towardthe surface S of the fluid in the fluid sump 12. A second leg 94 has aflowpath 94f and has a plurality of exit orifices 96 which extend in avertical direction for directing jets of fluid through the fluid, intothe air above and against the underside of the machine which is shown inFIG. 1 and FIG. 2.

The second conduit 86 has a first leg 98 having a flow path 98f whichextends into a region R of naturally lower circulation of the sump. Theconduit has a plurality of exit orifices, as represented by the arrows102 (angled at an angle of twenty (20) degrees to the direction of theflowpath in a horizontal plane and at an angle of twenty to twenty-five(20-25) degrees upwardly in a vertical plane). The exit orifices 102direct fluid away from the conduit 86 and upwardly toward the surface Sof the fluid in the fluid sump 12. A second leg 104 has a flowpath 104fand has a plurality of exit orifices 106 which extend in a verticaldirection for directing jets of fluid through the fluid, into the airabove and against the underside of the machine 10 which is shown in FIG.1 and FIG. 2.

Lines of flow F are shown in the sump 12. These lines of flow representone flow pattern for the metalworking fluid in the sump. The lines offlow extend through regions R of potentially low or no flow urgingmetalworking fluid to circulate in the sump. As a result, metalworkingfluid containing tramp oil is in flow communication with the remainingfluid in the sump. This insures that the tramp oil on the surface hashad an opportunity to move into a region adjacent the collectionchambers 48. As will be realized, the same orientation of fluid conduits84,86 for the same sump 12 may result in different flow patterns fordifferent machines. This results in part from contours of the differentmachines which distribute sprayed metalworking fluid to regions of thesump that differ from regions shown in FIG. 1 and from support structureof the different machines which might extend at other locations into thesump.

FIG. 4 is a side elevation view of a collection chamber 48 partiallybroken away to show the collection conduit 62 and a collection orifice52 disposed on the interior 54 of the chamber. In the embodiment shown,the wall 56 of the collection chamber is a curved surface and, inparticular, is cylindrical. In other embodiments, the wall might be oneof four walls forming a rectangle, a square or other shapes.

The cylindrical wall 56 extends circumferentially about the interior 54of the chamber 48. The cylindrical wall is disposed about an axis ofsymmetry A. A bottom 108 extends from the wall and seals the bottom ofthe collection chamber. In alternate embodiments, the bottom of thecollection chamber might be open with the bottom of the collectionchamber sealed by the bottom of the sump.

A plurality of cylindrical openings 58 extend through the wall 56. Theopenings 58 are circumferentially spaced one from the other. Theopenings 58 have a diameter which is approximately equal to one-thirdthe height of the collection chamber 48. Each cylindrical opening has acenter located at a position which is approximately level with the levelof coolant H in the sump 12 under normal operative conditions. In theembodiment shown, the collection chamber is approximately four andone-half inches high, has a cylindrical opening 58 having a diameter ofapproximately one and one-half inches and the center of the opening 58is approximately three inches from the bottom 108 of the chamber.

The collection chamber 48 includes a plurality of collection orifices 52that are in flow communication with the leg of the first collectionconduit 62. The collection orifices face in a predetermined directionfor sucking fluid from the collection chamber. The orifices are disposedat a level which is below the level of the opening in the wall. In theembodiment shown, the collection orifice to spaced less than one-half ofan inch (approximately three tenths of an inch) from the bottom surfaceof the opening. As shown the orifices face in a vertical direction awayfrom the bottom of the collection chamber.

FIG. 4A is a top view of the collection chamber 48. Lines of flow of themetalworking fluid are shown by arrows in the collection chamber. Asshown in FIG. 4A, the collection chamber has three orifices 52, two ofwhich are spaced ninety degrees from the third. Lines of flow in thechamber are represented by the arrows Fv showing formation of the vortexat each orifice. Lines Fc show general circulation within the collectionchamber that results in part from the flow Fv at the orifices.

FIG. 5 is a side elevation view of an alternate embodiment 48a of thecollection chamber 48 shown in FIG. 4. The collection chamber 48a has abottom 112 and a top 114. The first conduit 62a has a leg 64a extendingdown through the top of the collection chamber. In this embodiment, thecollection chamber has two orifices 52a spaced a distance below theopening 58 which is more than one inch. The orifices face in thehorizontal direction, that is, perpendicular to the wall 56. Experiencehas shown that a significantly greater flow rate is required toestablish a vortex than for the FIG. 4 embodiment.

FIG. 5A is a top view of the embodiment of the collection chamber 48ashown in FIG. 5 showing the vortex Fv and the lines of flow Fd.

FIG. 6 is an alternate embodiment 18a of the apparatus 18 for processingmetalworking fluid shown in FIG. 3. In FIG. 6, the circulation system 42includes an intermediate supply tank 116. A pump 118 suppliespressurized fluid to the fluid distribution system 14. The third conduit78a from the separator 22 having unpressurized clean fluid and thefourth conduit 82a having pressurized collected fluid are fed into theintermediate tank. The metalworking fluid in the tank has a tramp oilconcentration which is greater than the tramp oil concentration in thecollected fluid from the separator 22, but less than the tramp oilconcentration in collected fluid from the fourth conduit.

During operation of the apparatus 18 shown in FIG. 3, the apparatusprocesses the metalworking fluid. The collection region 55 is formed onthe interior 54 of the collection chamber 48 which has metalworkingfluid having a higher concentration of tramp oil than the concentrationof tramp oil in the sump 12. The orifices 52 of the collection chamberare disposed close to the surface of the fluid. Less metalworking fluidenters with the tramp oil. As a result, the tramp oil concentration ofthe fluid sucked in by the orifice 52,52a is even greater than theconcentration of tramp oil generally in the collection region, makingthe tramp oil concentration flowed to the separator 22 even greater thanthe concentration of tramp oil in the sump. Having provided the sumpwith a fluid distribution system 14 to circulate flow in the sump, theamount of collected fluid is divided in the circulation system 42between the separator and the fluid distribution system. The fluidreturned from the circulation system to the sump 12 through the fluiddistribution system provides pressurized fluid which is directed atregions of lower circulation.

In the embodiment shown, the fluid returned to the sump 12 may also beaerated by spraying the fluid into the air and against the machine 10 tofurther expose the fluid to air. The air contains oxygen and provides anunfriendly environment to anaerobic bacteria. In addition, the spraybreaks the surface S of the fluid, carrying oxygen back down through thetramp oil and into the metalworking fluid in the sump.

In the embodiment shown in FIG. 6, the metalworking fluid is flowed toan intermediate tank 116 which contains a reservoir of working mediumfluid. This reservoir of fluid is used to add fluid to the sump 12 bymeans of the pump 118. The flow rate of the pump is responsive to thelevel of coolant in the sump by conventional electrical, flow and/orpressure sensing means (not shown). This allows for the intermediatetank to supply fluid to the sump 12 should evaporation or heavy cuttingrequire the usage of increased levels of metalworking fluid which wouldlower the level of metalworking fluid in the sump 12 so that the levelfalls below the openings 58 to the collection chamber 48. This insuresthat the pump is constantly supplied with fluid and fluid continuouslyflows through the pump.

In either of the FIG. 3 or FIG. 6 embodiments, a particular advantage ofthe present invention is the ability to flow the required amount ofpressurized circulation fluid to the sump 12 and to tailor the flow toinsure that regions of low or no flow are avoided and to retard thegrowth of anaerobic bacteria which may spoil the metalworking fluid ordegrade its performance. As shown by the lines of circulation in FIG. 3,oil moves towards the collection chamber and the conduits, typicallymade of polyvinyl chloride (PVC) tubing, may be easily altered orflexibly oriented for installation or as required to provide fornecessary circulation.

The separator 22 has limited flow capacity and benefits from the twiceincreased concentration of tramp oil in the fluid flowed to theseparator. This increase in concentration of tramp oil results fromoperation of the collection chamber 48.

Another benefit of the collection chamber is the formation of vorticesin the collection chamber 48. These vortices combine to reinforce eachother in the collection chamber shown in FIG. 4 and causecircumferential circulation of the metalworking fluid in the chamber.The lighter tramp oil is forced inwardly by the more dense metalworkingfluid moving outwardly in response to this rotational movement of thefluid, This forces the lighter tramp oil to concentrate about the axisof the collection chamber where it is sucked into the orifice forprocessing at the separator 22. Another benefit is the ability to adjustthe size of the vortex by regulating flow. This controls the amount ofair the vortex entrains into the metalworking fluid. The valves and thusthe flow are adjusted to insure that the vortex does not ingest too muchair. Too much air would cause cavitation in the pump. Nevertheless, thevortex is big enough to provide the circulation described above forincreasing the tramp oil density in the collected flow.

Although the invention has been shown and described with respect todetailed embodiments thereof, it should be understood by those skilledin the art that various changes in form and detail thereof may be madewithout departing from the spirit and the scope of the claimedinvention.

What is claimed is:
 1. An apparatus for receiving metalworking fluidfrom a sump having a pool of such fluid, the sump having an operatinglevel of metalworking fluid having a height H under normal operativeconditions, which comprises:a collection chamber having an interior, thechamber being adapted to be disposed in the sump which includesat leastone wall extending about the interior of the chamber; at least twoopenings extending through the wall, the openings beingcircumferentially spaced one from the other and having a height in theinstalled condition which is at least one inch, each opening having alower surface which is located at a position which is at least one inchlower than the height H of the sump; a plurality of collection orificeswhich face in a predetermined direction for sucking fluid from theinterior of the collection chamber the orifices being disposed at alevel which is below the level of the lower surface of the opening, theorifices being in flow communication through the chamber with a meansfor sucking metalworking fluid from the chamber under operativeconditions;wherein the orifices are adapted to suck metalworking fluidfrom the interior of the collection chamber under operative conditionsat a predetermined flow rate.
 2. The apparatus as claimed in claim 1wherein the collection chamber has a top and a bottom and at least oneof the orifices of the collection chamber faces in the verticaldirection away from the bottom of the collection chamber.
 3. Theapparatus of claim 2 wherein the collection chamber has a bottom elementwhich seals the bottom of the collection chamber and has conduit meanswhich extend through the wall of the collection chamber which are inflow communication with the orifices in the collection chamber forsucking fluid from the collection chamber.
 4. The apparatus of claim 2wherein the collection chamber has a bottom element which seals thebottom of the collection chamber.
 5. The apparatus of claim 2 whereinthe orifices are vertically spaced from the openings in the collectionchamber by a distance which is less than one inch.
 6. The apparatus ofclaim 5 wherein the orifices are vertically spaced from the openings inthe collection chamber by a distance which is less than one half of aninch.
 7. The apparatus of claim 1 wherein at least one of the orificesof the collection chamber faces in a horizontal direction and areadjacent to the bottom of the collection chamber.
 8. The apparatus ofclaim 1 wherein the collection chamber has a top element which seals thetop of the collection chamber and has conduit means which extend throughthe top of the collection chamber which are in flow communication withthe orifices in the collection chamber for sucking fluid from thecollection chamber.
 9. The apparatus of claim 1 wherein the orifices arevertically spaced from the openings in the collection chamber apreselected distance and have a size and flow characteristic that adaptthe collection chamber to cause a vortex to form in the metalworkingfluid disposed in the chamber under operative conditions.
 10. Theapparatus of claim 1 wherein the orifices are vertically spaced from theopenings in the collection chamber by a distance which is less than oneinch.
 11. The apparatus of claim 1 wherein the openings in thecollection chamber are curved.
 12. The apparatus of claim 1 wherein theopenings in the collection chamber are slots.
 13. An apparatus forreceiving metalworking fluid from a sump for metalworking fluid having apool of such fluid, the sump having an operating level of metalworkingfluid having a height H under normal operative conditions, whichcomprises:a collection chamber having an interior, the chamber beingadapted to be disposed in the sump which includesa cylindrical wallextending circumferentially about the chamber which is disposed about anaxis of symmetry A; a bottom extending from the wall which seals thebottom of the collection chamber; a plurality of cylindrical openingextending through the wall, the openings being circumferentially spacedone from the other and having a diameter of approximately equal toone-third the height of the collection chamber, each cylindrical openinghaving a center located at a position which is approximately level withthe level of coolant in the sump under operative conditions; and aplurality of collection orifices which face in a predetermined directionfor sucking fluid from the interior of the collection chamber theorifices being disposed at a level which is below the level of theopenings in the wall, the orifices being in flow communication throughstructure of the chamber with means for sucking metalworking fluid fromthe chamber under operative conditions;wherein the orifices are adaptedto suck metalworking fluid from the interior of the collection chamberunder operative conditions at a predetermined flow rate.
 14. Thecollection chamber as claimed in claim 13 wherein the orifices face inan axial direction away from the bottom of the collection chamber. 15.The collection chamber of claim 13 wherein the orifices face in a radialdirection and are adjacent to the bottom of the collection chamber. 16.The collection chamber of claim 15 wherein the collection chamber has atop element which seals the top of the collection chamber and hasconduit means which extend through the top of the collection chamberwhich are in flow communication with the orifices in the collectionchamber for sucking fluid from the collection chamber.
 17. Thecollection chamber of claim 13 wherein the axial spacing of the orificesfrom the openings in the collection chamber is preselected to form avortex in metalworking fluid disposed in the chamber under operativeconditions.